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71.
The development of Watershed Management Plans (WMPs) in urban areas aids municipalities in allocating resources, engaging the public and stakeholders, addressing water quality regulations, and mitigating issues related to stormwater runoff and flooding. In this study, 124 urban WMPs across the United States were reviewed to characterize historic approaches and identify emerging trends in watershed planning. Planning methods and tools were qualitatively evaluated, followed by statistical analyses of a subset of 63 WMPs to identify relationships between planning factors. Plans developed by a municipality or consultant were associated with more occurrences of hydrologic modeling and site‐specific recommendations, and fewer occurrences of characterizing social watershed factors, than plans authored by agencies, organizations, or universities. WMPs in the past decade exhibited greater frequency in the use of pollutant load models and spatially explicit hydrologic and hydraulic models. Project prioritization was found to increasingly focus on feasibility to implement proposed strategies. More recent plans additionally exhibited greater consideration for water quality, ecological health, and public participation. Innovation in planning methods and consideration of future watershed conditions are primary areas that were found to be deficient in the study WMPs, although analysis methods and tools continue to improve in the wake of advancing technology and data availability.  相似文献   
72.
The aim of the study was to examine perceived job insecurity and its organizational antecedents and outcomes within a one‐year time period. The study was carried out by means of questionnaires, which were responded to twice, in 1995 (Time 1) and 1996 (Time 2), by employees in three organizations: a factory, a bank, and a municipal social and health care department. The present article is based on the data of those employees (n=210) who participated in the study in both years. The results indicated that perceived job insecurity varied with gender and organization, but not with time. In particular, female employees in the bank reported a high level of job insecurity compared with men. The use of a restorative strategy by management at Time 1 decreased job insecurity at Time 2, whereas job insecurity at Time 1 weakened the quality of human relations and perceived efficiency within the organizations at Time 2. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
73.
Environmental Management - This paper investigates the influence of using indigenous forecasts (IF) and scientific forecasts (SF) on arable farmers’ adaptation methods in the Rwenzori region,...  相似文献   
74.
Non-methane hydrocarbons (NMHCs) are known to have an important role on air quality due to their high reactivity. NMHC analysis has been performed on 148 ambient air samples collected at five different sites in the Kanto area (Tokyo metropolitan area and surrounding six prefectures) of Japan in summer and winter of 2008, and fifty NMHCs have been determined and quantified. A field measurement campaign has been conducted at one of the busiest intersections in Tokyo metropolitan area in winter of 2008. NMHC emissions are evaluated through comparison of distributions of individual NMHCs emitted from motor vehicles, which are estimated from the measurements, with those determined from the current emissions inventory. The comparison revealed that the measured distributions of acetylene, ethylene and toluene showed a good agreement with those estimated from the emissions inventory (the values estimated from the measurements are a factor of 1.5, 0.56 and 2.3 larger than the emissions inventory in median, respectively), however, propane and isobutane are found to be significantly underestimated in the emissions inventory (the measured values were a factor of 18 and 5.1 larger than the emissions inventory, respectively). The significant underestimate of propane can be explained by that the current emissions inventory does not consider emissions from liquefied propane gas (LPG) fueled vehicles. However, for isobutane, reasons for the underestimate are still unclear. Another field measurement has been conducted in summer of 2008, where the air samples have been collected at three different sites on the ground and by a helicopter as well. Remarkable high concentrations of 1-butene and cis- and trans-2-butenes have been sporadically observed in the samples collected at Urayasu in the coastal area of Tokyo bay. Calculated propylene equivalent (PE) concentrations of butenes revealed that those have a significantly important role in ozone formation when the air plume is affected by emissions from their emission sources. The PE concentrations of butenes varied from 0.1 to 39 ppbC, and accounted for 1.5–75% of total PE concentrations at Urayasu. Most of the continuous air quality monitoring stations does not record concentrations of individual hydrocarbons, therefore, the importance of reactive and low concentration hydrocarbon such as butenes might be overlooked in the current emissions inventory and/or air quality model. In this paper, the reliability of NMHC emissions is evaluated based on the field measurements. Their possible impacts on air quality in the Kanto area are discussed as well, based on the calculated propylene equivalent concentrations.  相似文献   
75.
Recently, great attention has been paid to the environmental problems in mining industry. At present there are different ways of mineral processing, as well as various methods of wastewater treatment, most of them are expensive. Work is ongoing to find low-cost treatments. In this article, low-cost adsorbents, potentially useful for wastewater treatment on mining and metallurgical plants, are reviewed; their characteristics, advantages, and disadvantages of their application are compared. Also adsorption of different metals and radioactive compounds from acidic environment similar to composition of mining and metallurgical wastewaters is considered.  相似文献   
76.
Understanding and managing ecosystems affected by several anthropogenic stressors require methods that enable analyzing the joint effects of different factors in one framework. Further, as scientific knowledge about natural systems is loaded with uncertainty, it is essential that analyses are based on a probabilistic approach. We describe in this article about building a Bayesian decision model, which includes three stressors present in the Gulf of Finland. The outcome of the integrative model is a set of probability distributions for future nutrient concentrations, herring stock biomass, and achieving the water quality targets set by HELCOM Baltic Sea Action Plan. These distributions can then be used to derive the probability of reaching the management targets for each alternative combination of management actions.  相似文献   
77.
78.
In order to investigate the compositions and wet deposition fluxes of trace elements and rare earth elements (REEs) in the precipitation of the southeastern edge of the Tibetan Plateau, 38 precipitation samples were collected from March to August in 2012 in an urban site of Lijiang city in the Mt. Yulong region. The concentrations of most trace elements and REEs were higher during the non-monsoon season than during the monsoon season, indicating that the lower concentrations of trace elements and REEs observed during monsoon had been influenced by the dilution effect of increased precipitation. The concentrations of trace elements in the precipitation of Lijiang city were slightly higher than those observed in remote sites of the Tibetan Plateau but much lower than those observed in the metropolises of China, indicating that the atmospheric environment of Lijiang city was less influenced by anthropogenic emissions, and, as a consequence, the air quality was still relatively good. However, the results of enrichment factor and principal component analysis revealed that some anthropogenic activities (e.g., the increasing traffic emissions from the rapid development of tourism) were most likely important contributors to trace elements, while the regional/local crustal sources rather than anthropogenic activities were the predominant contributors to the REEs in the wet deposition of Lijiang city. Our study was relevant not only for assessing the current status of the atmospheric environment in the Mt. Yulong region, but also for specific management actions to be implemented for the control of atmospheric inputs and the health of the environment for the future.  相似文献   
79.
80.
A retrieval system of mass spectra based upon the Probability Based Matching method was studied in order to apply it to survey the chemicals in environments by a gas chromatography-mass spectrometry-computer system. As retrieval indices, peak missing probability and relative confidence value were proposed.  相似文献   
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